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Despite being one of the most remote areas on the planet, the Antarctic continent is subject to anthropogenic influences. The presence of various groups of contaminants, including persistent organic pollutants (POPs) and polycyclic aromatic hydrocarbons (PAHs), has been documented in the region over the past decades. However, a significant knowledge gap remains regarding the detection of new pollutants, such as emerging contaminants (ECs), in Antarctic coastal environments. This study analyzed the occurrence and levels of selected POPs, PAHs, ECs in surface sediments from Admiralty Bay, Antarctica Peninsula. Non-target screening was employed to identify potential novel contaminants in the region. Samples (n = 17) were extracted using an accelerated solvent extraction (ASE) system and instrumental analyses were performed using gas chromatography coupled to a triple-quadrupole mass spectrometer (GC/MS-MS). Regarding regulated contaminants, concentrations of Σ5PCBs ranged from
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Cardiovascular diseases (CVDs) are the leading cause of death worldwide. This study focused on evaluating the impact of a Mediterranean-type diet combined with physical exercise on CVD risk factors of high-risk individuals. A randomized clinical trial (RCT) recruited individuals (≥50 years old) with no history of acute myocardial infarction, but with high CVD risk criteria according to the SCORE2/SCORE2 OP. Anthropometric and biochemical parameters were assessed at baseline and after 12 weeks of diet and exercise intervention. Participants were randomly assigned into 3 groups: no intervention group (Group 1a), physical exercise group (Group 1b), and physical exercise (±2 h/week) plus diet group (Group 2). Briefly, the dietary intervention was based on the principles of an isocaloric Mediterranean diet (MD), with seven main meals/week centered on plant-based foods (legumes and pulses). The combined effect of exercise and the diet showed significant decrease in WC (p = 0.002), BST (p < 0.001), visceral fat (p < 0.001), and TG (p = 0.029), compared with control groups. The intervention significantly increased legume intake (p < 0.001), as well as adherence to the MD, which associates with WC decrease (p = 0.024) and visceral fat (p = 0.017). A combined intervention of exercise and diet should be endorsed as an efficient modifier of cardiometabolic parameters.
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Enfermedades Cardiovasculares , Dieta Mediterránea , Ejercicio Físico , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Masculino , Femenino , Persona de Mediana Edad , Enfermedades Cardiovasculares/prevención & control , Anciano , Circunferencia de la Cintura , Factores de Riesgo , Grasa IntraabdominalRESUMEN
INTRODUCTION: Sporotrichosis is a subcutaneous mycosis caused by different species of thermodimorphic fungi belonging to the genus Sporothrix. These fungi may affect a wide range of warm-blooded animals, including humans, dogs and, mainly, cats. METHODS: In this article, we conducted a narrative literature review about the status of feline and cat-transmitted sporotrichosis in Latin American countries, with emphasis on Brazil. RESULTS: From a global perspective, Latin America is one of the main foci of human and feline sporotrichosis. In humans, the disease has been reported in several countries, with endemic transmission occurring in Brazil, Colombia, Costa Rica, Guatemala, Mexico and Uruguay. Sporothrix brasiliensis is the most common species identified in human cases in Brazil, whereas Sporothrix schenckii predominates in other countries. CONCLUSION: Domestic cats are the main source of infection in the zoonotic transmission cycle of sporotrichosis in Latin America. Cases of feline sporotrichosis have been reported in several countries, including Argentina, Brazil, Chile, Colombia, Mexico, Panama, Paraguay and Peru.
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This essay elucidates the Healthcare and Intersectionality notions to prompt reflections on the interaction between healthcare professionals and individuals referred to as Nanás: elderly, poor, and Black women who represent a historically marginalized profile throughout Brazilian history. By delving into the arguments about the concept of Intersectionality and the multifaceted Care dimensions, it becomes apparent that there is a pressing need to broaden the perspective on women who access healthcare services, as they are inherently shaped by their life experiences. Moreover, it is imperative to acknowledge how the intersecting factors inherent in their profiles can influence the approach taken by those providing Care, which underscores the essentiality of an intersectional agency on the part of the agents involved in this encounter, namely the Nanás and healthcare workers, to effectively uphold the principles of comprehensiveness and equity within the Unified Health System (SUS).
O presente ensaio articula os conceitos de Cuidado em Saúde e Interseccionalidade para suscitar reflexões sobre o encontro entre o/a trabalhador/a de saúde e aquelas que aqui denominamos uma Naná: uma mulher, negra, idosa e periférica, perfil historicamente vulnerabilizado ao longo da história brasileira. Considerando as argumentações que envolvem o conceito de Interseccionalidade e as diferentes vertentes acerca do Cuidado, observamos a necessidade de se ampliar o olhar sobre estas que buscam os serviços de saúde já atravessadas por suas histórias de vida, e ponderar sobre os atravessamentos que seu perfil pode acionar em quem exerce o Cuidado. Aponta ser primordial uma agência interseccional por parte das/os agentes deste encontro, Nanás e profissionais de saúde, para que se concretizem os princípios de integralidade e equidade no Sistema Único de Saúde (SUS).
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Atención a la Salud , Personal de Salud , Humanos , Brasil , Femenino , Atención a la Salud/organización & administración , Personal de Salud/psicología , Personal de Salud/organización & administración , Anciano , Población Negra/psicología , Pobreza , Poblaciones Vulnerables , Programas Nacionales de Salud/organización & administración , Accesibilidad a los Servicios de Salud , Disparidades en Atención de SaludRESUMEN
Several multiplex approaches for the simultaneous detection of pathogens in food have been developed in recent years, but the use of a single enrichment medium remains a problem. In this study, six enrichment broths (five non-selective media, tryptic soy broth (TSB), brain heart infusion broth (BHI), buffered peptone water (BPW), universal pre-enrichment broth (UPB), no. 17 broth, and a selective, Salmonella Escherichia Listeria broth (SEL)), were studied for the simultaneous detection of E. coli O157:H7, Salmonella spp., and L. monocytogenes, to validate the suitable enrichment broth to be used for the detection methods. Different ratios of E. coli O157:H7, Salmonella spp., and L. monocytogenes were used. Almost all non-selective broths evaluated in this study showed similar growth parameters and profiles among each other. The only selective enrichment broth under analysis (SEL) showed distinct growth features compared to the non-selective media, allowing for a slower but balanced growth of the three pathogens, which could be beneficial in preventing the overgrowth of fast-growing bacteria. In addition, when tested in ground beef samples, SEL broth seems to be the most distinctive medium with a balanced growth pattern observed for the three pathogens. Overall, this study is intended to provide the basis for the selection of suitable enrichment broths according to the technology detection to be used, the desired time of enrichment, and the expected balanced concentration of pathogens.
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AIM: To compare the effects of Cervical Access Cavity (CervAC) and Traditional Access Cavity (TradAC) on root canal preparation, root canal filling, and fracture resistance in mandibular incisors. METHODOLOGY: Twenty recently extracted and intact mandibular incisors were initially scanned using a micro-CT device. The specimens were anatomically matched to create two groups (n = 10). A wedge-shaped non-carious cervical lesion (NCCL) was created on the buccal aspect of all teeth using a double-faced segmented diamond disc. In group 1, a TradAC was prepared, whilst in group 2, access was created through the simulated NCCL using a round diamond bur 1012. After root canal preparation with Rotate instruments sizes 15/0.04, 20/0.04, and 25/0.04, the teeth were scanned again and evaluated for root canal volume and surface area, static voxels, volume of removed dental tissue, and dentine thickness. After that, the root canals were filled using the single-cone technique, teeth were restored with composite resin, and subsequently rescanned to calculate the volume of filling materials and voids. Then, the restored teeth were subjected to fracture resistance tests using a universal testing machine. Statistical comparisons between groups were performed with the Mann-Whitney test or the Student's t-test, with a statistical significance level of 5%. RESULTS: Statistical comparisons indicated no significant differences between groups in terms of root canal volume, surface area, static voxels, removed root dentine, root canal filling volume, percentage of voids, or fracture resistance load (p > .05). Conversely, teeth prepared with TradAC showed a significantly higher percentage of dental tissue removed from the crown (p = .001) and a greater volume of filling material remnants in the pulp chamber (p < .001) compared to the CervAC group. A significantly lower percentage reduction in dentine thickness was observed only on the mesial aspect of root at Level 1 in TradAC group (p = .008). CONCLUSIONS: CervAC can be considered a viable alternative approach in the presence of NCCL in mandibular incisors.
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To ensure unbiased tree-ring radiocarbon (14C) results, traditional pretreatments carefully isolate wood cellulose from extractives using organic solvents, among other chemicals. The addition of solvents is laborious, time-consuming, and can increase the risk of carbon contamination. Tropical woods show a high diversity in wood-anatomical and extractive composition, but the necessity of organic-solvent extraction for the 14C dating of these diverse woods remains untested. We applied a chemical treatment that excludes the solvent step on the wood of 8 tropical tree species sampled in South-America and Africa, with different wood-anatomical and extractive properties. We analyzed the success of the extractive removal along with several steps of the α-cellulose extraction procedure using Fourier Transform Infrared (FTIR) spectroscopy and further confirmed the quality of 14C measurements after extraction. The α-cellulose extracts obtained here showed FTIR-spectra free of signals from various extractives and the 14C results on these samples showed reliable results. The chemical method evaluated reduces the technical complexity required to prepare α-cellulose samples for 14C dating, and therefore can bolster global atmospheric 14C applications, especially in the tropics.
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Celulosa , Madera , Madera/química , Celulosa/química , Espectroscopía Infrarroja por Transformada de Fourier , Clima Tropical , Radioisótopos de Carbono/análisis , Árboles , Monitoreo del Ambiente/métodos , Datación Radiométrica/métodosRESUMEN
The Brazil-Malvinas Confluence (BMC) is a significant biological frontier where distinct currents meet, fostering optimal conditions for phytoplankton development. In this study we tested the hypothesis that eddys promote an increase in phytoplankton biomass at the Brazil-Malvinas Confluence (BMC), altering species diversity. Phytoplankton were collected with Niskin bottles and nutrient concentrations assessed at two depths (Surface and Deep Chlorophyll Maximum Layer - DCML) in areas outside and under the influence of Cold-Core (CCE) and Warm-Core (WCE) Eddies. Environmental variables were determined in situ using a CTD profiler. Four regions were separated based on environmental variables and phytoplankton species, namely, the Brazil Current (BC), Malvinas Current (MC), CCE, and WCE. Species diversity was higher in the eddies. The conditions of the WCE were different from those of the CCE, with low temperature and salinity and high cell density values in the latter. The phylum Bacillariophyta was predominant in terms of species richness in all regions and was responsible for the higher cell density in the MC, while dinoflagellates were dominant in the BC and eddies. Therefore, eddy activity alters the structure, diversity and biomass of the phytoplankton community in the BMC.
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Biodiversidad , Biomasa , Fitoplancton , Fitoplancton/clasificación , Fitoplancton/crecimiento & desarrollo , Brasil , Estaciones del Año , Clorofila/análisis , Movimientos del Agua , TemperaturaRESUMEN
Future trajectories of agricultural productivity need to incorporate environmental targets, including the reduction of pesticides use. Landscape features supporting natural pest control (LF-NPC) offer a nature-based solution that can serve as a partial substitute for synthetic pesticides, thereby supporting future productivity levels. Here, we introduce a novel approach to quantify the contribution of LF-NPC to agricultural yields and its associated economic value to crop production in a broad-scale context. Using the European Union as case study, we combine granular farm-level data, a spatially explicit map of LF-NPC potential, and a regional agro-economic supply and market model. The results reveal that farms located in areas characterized by higher LF-NPC potential experience lower productivity losses in a context of reduced synthetic pesticides use. Our analysis suggests that LF-NPC reduces yield gaps on average by four percentage points, and increases income by a similar magnitude. These results highlight the significance of LF-NPC for agricultural production and income, and provide a valuable reference point for farmers and policymakers aiming to successfully invest in landscape features to achieve pesticides reduction targets.
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Agricultura , Productos Agrícolas , Unión Europea , Granjas , Plaguicidas , Agricultura/economía , Agricultura/métodos , Productos Agrícolas/economía , Renta , Control Biológico de Vectores/métodos , Control Biológico de Vectores/economía , Producción de Cultivos/economía , Producción de Cultivos/métodos , Control de Plagas/economía , Control de Plagas/métodosRESUMEN
DEMETER-Like DNA demethylases (DMLs) are epigenetic regulators of many developmental and biological processes in plants. No comprehensive information about the DML gene family in citrus is available to date. Here, a total of three DML genes in the genomes of Citrus sinensis (named CsDML1-3) and C. clementina (named CcDML1-3) were identified and analyzed. They encode hydrophilic and relatively large proteins, with prediction of nuclear localization, containing the conserved domains and motifs typical of plant DMLs. Protein interaction network analysis suggested that they interact primarily with proteins related to the maintenance of DNA methylation and remodeling of chromatin. Analysis of their promoter regions led to the identification of several cis-acting regulatory elements involved in stress response, including drought, heat and cold stresses. The presence of several miRNA targets and potential phosphorylation sites suggest that their expression is also regulated at post-transcriptional and post-translational levels. RNA-Seq data and quantitative real-time PCR analysis showed a low and drought-regulated gene expression of the citrus DMLs in different plant tissues. CsDML1 and CsDML3 were also differentially regulated by deficit irrigation in fruits at different developmental stages, with a positive and significant correlation found between CsDML1 and PHYTOENE SYNTHASE (PSY) and between CsDML3 and ATP CITRATE LYASEs (ACLs) and ZETA-CAROTENE DESATURASE (ZDS) gene expression. These results indicate that the citrus DMLs are potentially functional enzymes involved in developmental processes and drought stress-adaptive responses, providing a useful reference for further investigation of their functions and applications on the citrus improvement.
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This study assessed canal preparation effects on disinfection and dentin preservation. Thirty mandibular incisors were paired into two experimental groups (n = 10). Following contamination, the initial microbial sample was collected. Instruments 30/0.03 (Group 1) and 30/0.05 (Group 2) were employed and a second sample was obtained. Canals were enlarged using instruments 40/0.03 and 40/0.05, respectively, and a third sample was collected. Final irrigation was performed, and sample S4 obtained. A final scan evaluated volume, surface area, unprepared areas, removed dentin and dentin thickness. Data were analysed using Student t-test, Mann-Whitney, Kruskal-Wallis and Dunn tests. A significant difference was observed between S1 and other time points (p < 0.05). Comparison between groups showed no differences in bacterial loads and in the percentage of microbial reduction (p > 0.05). Group 2 exhibited greater reduction in dentin thickness than group 1 in the mesial aspect of the root (p < 0.05). Instrument 30/0.03 might provide effective disinfection and safety during mandibular incisors canal preparation.
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Desinfección , Incisivo , Mandíbula , Preparación del Conducto Radicular , Humanos , Preparación del Conducto Radicular/instrumentación , Preparación del Conducto Radicular/métodos , Desinfección/métodos , Cavidad Pulpar/microbiología , Diseño de Equipo , Dentina/microbiología , Carga BacterianaRESUMEN
Osteosarcoma conventional chemotherapeutics are known for their side effects, limited options, and induction of drug resistance. This creates the need to develop new therapeutics capable of effectively destroying cancer cells with low toxicity, improving patient survival rate and their life quality. This work reports a novel drug delivery nanoplataform made of Natural Melanin Nanoparticles (MNPs), obtained from Sepia officinalis ink, with 99% incorporation efficiency of doxorubicin (Dox) without the use of non-toxic solvents. A significant photothermal effect was shown by a 36ºC increment after 10â¯min of laser irradiation, surpassing reported values for synthetic melanin. A sustained drug release of ca. 23% with photothermal stimuli was observed, compared to 15% without stimuli, after 48â¯h. This nanoplatform is obtained as a food industry side product, which makes it a natural cost-effective biomedical material. Natural MPs were applied in an osteosarcoma cell line (SaOs-2), and internalized by the cells in less than 2â¯h, showing cytocompatibility up to 1000⯵g/mL after 72â¯h of contact with cells. On the contrary, when natural MNPs loaded with Dox (Dox-MNPs) were placed in contact with the SaOs-2 cells and were simultaneously receiving NIR light it was observed a 93% reduction in cancer cells in 48â¯h, revealing a synergistic effect between chemotherapy and phototherapy. To our knowledge this is the first time that natural MNPs extracted from Sepia officinalis were tested on an osteosarcoma cell line as chemo-photothermal agent, showing these NPs are an effective, cost-effective, reproducible, non-toxic nanoplatform for osteosarcoma treatment using combined effects.
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Supervivencia Celular , Doxorrubicina , Melaninas , Nanopartículas , Osteosarcoma , Sepia , Humanos , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/patología , Doxorrubicina/farmacología , Doxorrubicina/química , Melaninas/metabolismo , Nanopartículas/química , Sepia/química , Supervivencia Celular/efectos de los fármacos , Línea Celular Tumoral , Liberación de Fármacos , Antibióticos Antineoplásicos/farmacología , Antibióticos Antineoplásicos/química , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/patología , Tamaño de la Partícula , Análisis Costo-Beneficio , Ensayos de Selección de Medicamentos AntitumoralesRESUMEN
There has been considerable discussion regarding the environmental life cycle of Legionella pneumophila and its virulence potential in natural and man-made water systems. On the other hand, the bacterium's morphogenetic mechanisms within host cells (amoeba and macrophages) have been well documented and are linked to its ability to transition from a non-virulent, replicative state to an infectious, transmissive state. Although the morphogenetic mechanisms associated with the formation and detachment of the L. pneumophila biofilm have also been described, the capacity of the bacteria to multiply extracellularly is not generally accepted. However, several studies have shown genetic pathways within the biofilm that resemble intracellular mechanisms. Understanding the functionality of L. pneumophila cells within a biofilm is fundamental for assessing the ecology and evaluating how the biofilm architecture influences L. pneumophila survival and persistence in water systems. This manuscript provides an overview of the biphasic cycle of L. pneumophila and its implications in associated intracellular mechanisms in amoeba. It also examines the molecular pathways and gene regulation involved in L. pneumophila biofilm formation and dissemination. A holistic analysis of the transcriptional activities in L. pneumophila biofilms is provided, combining the information of intracellular mechanisms in a comprehensive outline. Furthermore, this review discusses the techniques that can be used to study the morphogenetic states of the bacteria within biofilms, at the single cell and population levels.
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Nisin A is a lantibiotic bacteriocin typically produced by strains of Lactococcus lactis. This bacteriocin has been approved as a natural food preservative since the late 1980â¯s and shows antimicrobial activity against a range of food-borne spoilage and pathogenic microorganisms. The therapeutic potential of nisin A has also been explored increasingly both in human and veterinary medicine. Nisin has been shown to be effective in treating bovine mastitis, dental caries, cancer, and skin infections. Recently, it was demonstrated that nisin has an affinity for the same receptor used by SARS-CoV-2 to enter human cells and was proposed as a blocker of the viral infection. Several nisin variants produced by distinct bacterial strains or modified by bioengineering have been described since the discovery of nisin A. These variants present modifications in the peptide structure, biosynthesis, mode of action, and spectrum of activity. Given the importance of nisin for industrial and therapeutic applications, the objective of this study was to describe the characteristics of the nisin variants, highlighting the main differences between these molecules and their potential applications. This review will be useful to researchers interested in studying the specifics of nisin A and its variants.
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Antibacterianos , Nisina , Nisina/química , Nisina/farmacología , Humanos , Animales , Antibacterianos/farmacología , Antibacterianos/química , Lactococcus lactis/metabolismo , Lactococcus lactis/genética , Bovinos , SARS-CoV-2/efectos de los fármacos , Tratamiento Farmacológico de COVID-19RESUMEN
Invasive species significantly impact biodiversity and ecosystem services, yet understanding these effects at large spatial scales remains a challenge. Our study addresses this gap by assessing the current and potential future risks posed by 94 invasive species to seven key ecosystem services in Europe. We demonstrate widespread potential impacts, particularly on outdoor recreation, habitat maintenance, crop provisioning, and soil and nitrogen retention. Exposure to invasive species was higher in areas with lower provision of ecosystem services, particularly for regulating and cultural services. Exposure was also high in areas where ecosystem contributions to crop provision and nitrogen retention were at their highest. Notably, regions vital for ecosystem services currently have low invasion suitability, but face an average 77% increase in potential invasion area. Here we show that, while high-value ecosystem service areas at the highest risk represent a small fraction of Europe (0-13%), they are disproportionally important for service conservation. Our study underscores the importance of monitoring and protecting these hotspots to align management strategies with international biodiversity targets, considering both invasion vulnerability and ecosystem service sustainability.
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Ecosistema , Especies Introducidas , Biodiversidad , Conservación de los Recursos Naturales , Europa (Continente) , Nitrógeno , AnimalesRESUMEN
BACKGROUND: Polyurethane (PU)-coated breast implants are known for their strong integration into breast tissue and the formation of capsules around them. However, capsular contracture can pose both aesthetic and clinical challenges. OBJECTIVES: The objectives of this study were to analyze the biological and morphological characteristics of the capsular tissue surrounding PU-coated implants, irrespective of their contracture status, and to assess their potential suitability as a flap in revisional breast surgery for capsular contracture. METHODS: A total of 23 tissue samples were harvested from the capsules surrounding PU-coated breast implants in 12 female patients during replacement or revisional surgery. We evaluated collagen abundance, cellular and vascular density, inflammation, collagen band types and alignment, synovial metaplasia, capsule thickness, and the expression of inflammatory biomarkers and myofibroblasts with immunohistochemical techniques. Scanning electron microscopy was employed to assess implant surface characteristics over time. RESULTS: We found a significant association of capsule contraction with longer implantation durations and greater implant surface roughness (P = .018 and P = .033, respectively). Synovial metaplasia was significantly more frequent in noncontracted capsules (P = .0049). Both capsule types consisted of paucicellular, type I collagen-rich compact fibrous tissue with low vascularization. There was a marked reduction in inflammatory cells within the foreign body granuloma. The expression of inflammatory biomarkers in the capsular tissue was negligible. CONCLUSIONS: Given the reduced levels of inflammatory and vascular components within the dense, fibrous capsular tissue, we consider them to be viable alternatives for capsular flaps in revisional surgery. This strategy has the potential to mimic the reconstruction achieved with acellular dermal matrix.
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Implantación de Mama , Implantes de Mama , Contractura Capsular en Implantes , Poliuretanos , Humanos , Femenino , Implantes de Mama/efectos adversos , Adulto , Persona de Mediana Edad , Implantación de Mama/efectos adversos , Implantación de Mama/instrumentación , Implantación de Mama/métodos , Contractura Capsular en Implantes/etiología , Contractura Capsular en Implantes/patología , Reoperación , Materiales Biocompatibles Revestidos , Propiedades de Superficie , Factores de Tiempo , Microscopía Electrónica de Rastreo , Diseño de Prótesis , Metaplasia/patologíaRESUMEN
The use of Intravascular Laser Irradiation of Blood (ILIB) as a treatment or adjunct tool has been used around the world since the 1980s. So that more professionals can deliver benefits to their patients in different areas of health, it is necessary to understand in depth the mechanisms of laser action at the molecular level, for correct indication and success in the treatment. To analyze works that evaluated the influence of ILIB on inflammatory cytokines and nitric oxide (NO) in animals and humans. The literature search was carried out between February and April 2023 in Pubmed, Medline, Web of Science, SciELO, Lilacs database. The risk of bias was assessed using the bias table where the authors performed the analyzes of all articles with the risk of bias domains. The methodology was defined following the PRISMA guidelines (Preferred Systematic Reviews and MetaAnalysis Report). The search retrieved 135 possibly relevant articles. After removing duplicates, according to the eligibility criteria, evaluation of titles and review of abstracts, in the end, 6 articles were included. An increase in anti-inflammatory cytokines, a decrease in pro-inflammatory cytokines and an increase in NO can be observed. The wavelengths used ranged from 660 to 808 nm when using a low intensity laser and when using a VIP light source 480-3400 nm, they also differed in terms of the light emission pattern. ILIB may be a complementary treatment option for patients who have comorbidities that lead to systemic inflammation.
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Citocinas , Óxido Nítrico , Animales , Humanos , Inflamación/radioterapiaRESUMEN
Salmonella spp. is among the most central etiological agents in foodborne bacterial disorders. To identify Salmonella spp., numerous new molecular techniques have been developed conversely to the traditional culture-based methods. In this work, a new peptide nucleic acid fluorescence in situ hybridization (PNA-FISH) method was developed for the specific detection of Salmonella species, allowing a faster analysis compared with the traditional methods (ISO 6579-1: 2017). The method was optimized based on a novel PNA probe (SalPNA1692) combined with a blocker probe to detect Salmonella in food samples through an assessment of diverse-rich and selective enrichment broths. Our findings indicated that the best outcome was obtained using a 24-h pre-enrichment step in buffered peptone water, followed by RambaQuick broth selective enrichment for 16 h. For the enrichment step performance validation, fresh ground beef was artificially contaminated with two ranges of concentration of inoculum: a low level (0.2-2 colony-forming units [CFUs]/25 g) and a high level (2-10 CFUs/25 g). The new PNA-FISH method presented a specificity of 100% and a detection limit of 0.5 CFU/25 g of food sample, which confirms the great potential of applying PNA probes in food analysis.
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Microbiología de Alimentos , Hibridación Fluorescente in Situ , Ácidos Nucleicos de Péptidos , Salmonella , Hibridación Fluorescente in Situ/métodos , Salmonella/aislamiento & purificación , Salmonella/genética , Microbiología de Alimentos/métodos , Animales , Contaminación de Alimentos/análisis , Bovinos , Sensibilidad y Especificidad , Límite de Detección , Carne Roja/microbiologíaRESUMEN
Hematopoietic stem cells (HSCs) produce all essential cellular components of the blood. Stromal cell lines supporting HSCs follow a vascular smooth muscle cell (vSMC) differentiation pathway, suggesting that some hematopoiesis-supporting cells originate from vSMC precursors. These pericyte-like precursors were recently identified in the aorta-gonad-mesonephros (AGM) region; however, their role in the hematopoietic development in vivo remains unknown. Here, we identify a subpopulation of NG2+Runx1+ perivascular cells that display a sclerotome-derived vSMC transcriptomic profile. We show that deleting Runx1 in NG2+ cells impairs the hematopoietic development in vivo and causes transcriptional changes in pericytes/vSMCs, endothelial cells and hematopoietic cells in the murine AGM. Importantly, this deletion leads also to a significant reduction of HSC reconstitution potential in the bone marrow in vivo. This defect is developmental, as NG2+Runx1+ cells were not detected in the adult bone marrow, demonstrating the existence of a specialised pericyte population in the HSC-generating niche, unique to the embryo.
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Células Endoteliales , Músculo Liso Vascular , Ratones , Animales , Músculo Liso Vascular/metabolismo , Células Endoteliales/metabolismo , Diferenciación Celular , Células Madre Hematopoyéticas/metabolismo , Hematopoyesis/genética , Mesonefro , Gónadas/metabolismo , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismoRESUMEN
In this study, we present a comprehensive atmospheric radiocarbon (14C) record spanning from 1940 to 2016, derived from 77 single tree rings of Cedrela odorata located in the Eastern Amazon Basin (EAB). This record, comprising 175 high-precision 14C measurements obtained through accelerator mass spectrometry (AMS), offers a detailed chronology of post-1950 CE (Common Era) 14C fluctuations in the Tropical Low-Pressure Belt (TLPB). To ensure accuracy and reliability, we included 14C-AMS results from intra-annual successive cuts of the tree rings associated to the calendar years 1962 and 1963 and conducted interlaboratory comparisons. In addition, 14C concentrations in 1962 and 1963 single-year cuts also allowed to verify tissue growth seasonality. The strategic location of the tree, just above the Amazon River and estuary areas, prevented the influence of local fossil-CO2 emissions from mining and trade activities in the Central Amazon Basin on the 14C record. Our findings reveal a notable increase in 14C from land-respired CO2 starting in the 1970s, a decade earlier than previously predicted, followed by a slight decrease after 2000, signaling a transition towards the fossil fuel era. This shift is likely attributed to changes in reservoir sources or global atmospheric dynamics. The EAB 14C record, when compared with a shorter record from Muna Island, Indonesia, highlights regional differences and contributes to a more nuanced understanding of global 14C variations at low latitudes. This study not only fills critical spatial gaps in existing 14C compilations but also aids in refining the demarcation of 14C variations over South America. The extended tree-ring 14C record from the EAB is pivotal for reevaluating global patterns, particularly in the context of the current global carbon budget, and underscores the importance of tropical regions in understanding carbon-climate feedbacks.